One challenge, faced during the construction of roads, buildings, and other similar structures, is the need to safely perform the work while allowing traffic and pedestrians access to surrounding facilities. In an urban environment, this may mean providing for pedestrian traffic adjacent to such construction. It may also be important to allow vehicle traffic continued access to roadways undergoing or adjacent to such construction. In each of these situations, the pedestrians or vehicles may need to be guided onto portions of the roadway which may not normally be used for pedestrian or vehicle traffic, such as the area used for parking or opposing vehicle lanes. To safely do this, vehicles and pedestrians need to be channeled and guided into and onto the new pathway. Furthermore, in instances where pedestrians and vehicles are using adjacent pathways, the pedestrians and vehicles need to be separated to ensure that there are no pedestrian/vehicle encounters and conflicts.
A variety of devices have been used to provide pedestrian/vehicle separation, including cones, drums, and stanchions connected with chains or ropes. One system that provides effective separation is a continuous line of barriers known as Longitudinal Channelizing Devices (LCDs). LCDs provide a continuous line of demarcation between where the vehicles should travel and where the pedestrians should walk. A typical LCD may be configured as a short barrier that may be connected to an adjacent barrier, via a pin, or similar type of connector. Additional barriers may be added to define a continuous barrier system. The connection between barriers ensures that the barriers remain connected should they be bumped or jostled. Compliance at the joints between adjacent barriers may allow the barrier system to follow a curved or curvilinear path. Typically, it is desirable to provide LCDs with high visibility, for example by configuring the LCDs with bright, contrasting colors, such as orange and white. To maintain their position, LCDs may be ballasted with water or sand.
LCDs may be used in situations where there is vehicular traffic on one side and pedestrians on the other, or with vehicular traffic on both sides. In situations where pedestrians are passing along one side of the barrier, the barrier needs to be designed to accommodate the diverse needs of pedestrians, as called for in the Americans with Disabilities Act Accessibility Guidelines (ADAAG) and the Manual on Uniform Traffic Control Devices (MUTCD). For example, an individual who is sight impaired may need a continuous hand rail along the top of the barrier, regardless of whether the barrier system follows a straight or curvilinear path.
A sight impaired person who uses a cane may also require a continuous vertical surface near the ground, again regardless of whether the barrier system follows a straight or curvilinear path. For example, the MUTCD calls for continuous bottom and top surfaces that are detectable to users of long canes. The bottom surface needs to be no higher than 2 inches above the ground and the top surface needs to be no lower than 32 inches above the ground. The MUTCD also states that the barrier needs to provide a continuous vertical surface up to at least 6 inches above the ground.
Some barriers are configured with an internal steel frame, and/or with an external steel cables and steel connector pins. Such configurations may be expensive to manufacture. Some barriers may also have limited compliance at the joint between adjacent barriers, which precludes use of the system along a curved pathway, especially where the curvature is defined by a small radius.
Other devices may have better joint compliance, but fail to provide continuity along a top surface, or to provide to provide a continuous vertical surface near the ground, when deployed in an articulated configuration, for example along a curvilinear path. Other barriers may provide a continuous upper surface to act as a hand guide, as well as a continuous vertical surface near the ground, but are not self-ballasted, meaning the barriers may be easily displaced once deployed. Some barriers may be ballasted with sand, but are difficult to empty after use, and barriers relying on sand bags for ballast are messy and subject to tampering.